By pull-down bed, do you mean upper-bunk bed? I think I do see an upper bunk in the photos of the 9 a's (it is still tucked up in the ceiling above the couch). What I do NOT see is a privacy curtain. There is also not a split bath, it is one all-in-one bathroom.
I think the extra $100 would be worth it to switch to 8D. The 8 d's are all aft, none forward. If you can choose your stateroom number, choose one as far to the middle as you can. I've never felt sea-sick aft, myself....it is always forward that does me in. My DH notices a slight vibration aft, but that vibration does not make me queasy, so it doesn't bother me. I have no idea if the Fantasy will have a vibration aft...but many cruise ships do. I like aft

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You will get a bigger porthole (than the 9 a's) and they have a built in seat that looks great! You will have a privacy curtain and a splitbath. Your wall will not slant. Win, win, win

. Good luck!